PartIV Close

For thousands of years, people thought of glass as something beautiful to look at. Only recently 71 come to 72 something look through. Stores 73 their goods in large glass windows. Glass bottles and jars 74 food and drink allow us 75 the contents. Glass 76 spectacles(眼镜), microscopes, telescopes, and 77 very useful and necessary objects, 78 glasses, are used by people who cannot see 79 or by people who want to protect their eyes 80 bright light. Microscopes make tiny things larger 81 we can examine them. Telescopes 82 objects that are far away appear 83 closer to us. 

84 in recent years plastics have replaced glass 85 conditions where glass might be 86 broken there are new uses 87 for glass that were never imagined in the 88. Perhaps the greatest 89 of glass is that its constituent(形成的) parts are inexpensive and can be found 90 over the world.   

71. A. they                 B. do they       C. they have      D. have they 
72. A. think it             B. think if of    C. think it as      D. think of it as 
73. A. protect             B. hide            C. display          D. set aside 
74. A. hold                 B. held            C. that hold       D. that holding 
75. A. see                   B. to see         C. seeing           D. seen 
76. A. used to make  B. is used to mak C. is used to making D. used to making  

77. A. many others    B. many other    C. else             D. another 
78. A. and                  B. as well        C. or                 D. either 
79. A. perfectly           B. perfect        C. perfection      D. perfected 
80. A. from                B. in                C. with              D. beyond